socket_set_nonblock

Description

boolsocket_set_nonblock
( resource$socket
)

The socket_set_nonblock() function sets the
O_NONBLOCK flag on the socket specified by
the socket parameter.

When an operation (e.g. receive, send, connect, accept, ...) is performed on
a non-blocking socket, the script will not pause its execution until it receives a
signal or it can perform the operation. Rather, if the operation would result
in a block, the called function will fail.

Return Values

Examples

This example creates a listening socket on all interfaces on port 1223 and
sets the socket to O_NONBLOCK mode.
socket_accept() will immediately fail unless there is a
pending connection exactly at this moment.

User Contributed Notes 1 note

Beware, when using this function within a loop (i.e. a demon with a socket). The socket_accept(), for example, emits a warning each time there is no incoming connection available to be read. My php error log file got huge in a matter of seconds, eventually crashing the server.

Of course, i used the @ before the function to take care of that problem.

[EDITOR: One can (and should) use socket_select to detect a new connection on a socket (it's a "readable" event)]